The half-life of everything: From caffeine to knowledge

How to survive and thrive in a world of changing facts?

A friend once gave me a quirky tip: sip grapefruit juice with your caffeine before a marathon. The reason? Grapefruit juice slows down how quickly your body processes caffeine, so the buzz lasts longer. Perfect for powering through those 26.2 miles! ☕️⚡️

But before you gulp down that citrusy concoction, let's talk about why this works. It all comes down to something you might remember from high school science: half-life.

The half-life of caffeine (and other things we love)

Caffeine has a half-life of around 6 hours. That means if you have a cup of coffee, half of it is still buzzing through your system six hours later.

Another six hours, and half of that is still in you. And so on... It can take a full 24 hours for caffeine to leave your body entirely.

Remember learning about half-life in school? Maybe it was about radioactive materials or something equally thrilling. 🥱

Half-life is the time it takes for half of something to decay or break down.

For caffeine, it's about keeping you alert longer. For uranium, it could be about waiting a million years to turn into something less terrifying. ☢️

Interestingly, the concept of half-life goes beyond just caffeine or uranium.

The half-life of knowledge

Just like caffeine and atoms, knowledge has its own half-life. The facts we cling to today might not hold up tomorrow. One day, butter is evil. Next, it’s a misunderstood hero. One minute, Pluto is a planet, then it isn’t, and who knows what’s next?

Marketing campaigns, programming languages, medical discoveries—they all have a shelf life.

The half-life of facts is the time it takes for half of what we know to be proven wrong. The more we learn, the more some of what we learned becomes outdated.

"Many medical schools inform their students that within several years half of what they’ve been taught will be wrong, and the teachers just don’t know which half."
— Samuel Arbesman, author of The Half-Life of Facts: Why Everything We Know Has an Expiration Date

So, how do we cope with this ever-shifting landscape of knowledge?

How to deal with when the facts keep changing?

Embrace it.

Instead of being frustrated when something you thought was true turns out to be false, see it as a sign of growth. We’re constantly getting better at understanding the world, and that’s good!

Think of it like a marathon, but in the race for knowledge, we’re all pacing ourselves for a course that’s always changing.

Knowing this, what should our kids really be learning in school? Which professions have a longer “half-life” of relevance? And what books should we read—ones that will be outdated in five years, or ones that have stood the test of centuries?

Picking your battles wisely

When it comes to growing in a fast-paced world, learning becomes your secret weapon. Knowing that some of what you learn will become obsolete can actually be freeing—it pushes you to stay curious, keep exploring, and never settle.

My daughter’s biology teacher recently reminded her class that much of what they learn will soon be obsolete. Far from being discouraging, this pushes them to always be curious, always be learning using resources other than textbooks printed a few years back.

After all, wouldn’t it be boring if everything stayed the same?

So, whether you’re sipping on grapefruit juice to stretch your caffeine high or diving into discoveries with an open mind, remember: change is the only constant. Embrace it, learn from it, and let it fuel your next adventure.

Who knows? Tomorrow, you might learn something that changes everything you know today.

"Imagine what you'll know tomorrow."
— Tommy Lee Jones

Until next time! 😊